Synergistic combination of fungicides to protect wood and wood-based products and wood treated by such combination as well as methods of making the same

ABSTRACT

A wood treatment composition having a synergistic combination of fungicides which may include two or more compounds. These combinations are shown to be especially effective in providing resistance to decay, mold and mildew when wood is treated with these combinations. Also provided is wood treated by these combinations, and a method of treatment for composite wood.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to synergistic combinations of fungicides which,when applied to wood, give a synergistic result in providing improvedresistance to mold, mildew and fungal decay. Wood treated with thiscombination, and a method of treating wood, are also included in thepresent invention.

2. Description of the Prior Art

Wood is one of the best structural materials for the construction ofbuildings because of its strength, ease of processing and relatively lowcost. However, wood and wood-based materials, including cellulosiccomposites and plastic-wood composites, are susceptible to attack fromvarious fungal organisms. Fungal attack can result in cosmetic damage(stain, mold and mildew) and/or structural degradation (decay) to bothsolid wood and wood-based composites.

Mold organisms, in addition to marring the appearance of wood, canpresent a health hazard in indoor environments since certain mold sporeshave the potential to be human respiratory allergens.

Sapstain is a particular problem for freshly sawn green lumber. Althoughattack by sapstain fungi does not generally result in the reduction ofstrength properties, sapstain can seriously degrade the value of lumberby impairing its appearance.

Preservative chemicals have been used since antiquity to prevent theonset of mold, stain and decay to wood in service. In recent times, theuse of some wood preserving chemicals has been restricted or curtaileddue to concerns about their safety to humans and their effects on theenvironment. Cost effectiveness of preservative treatments is also amajor consideration since wood ultimately competes with non-cellulosicconstruction materials including steel, plastic and concrete.

Currently, a variety of fungicides are available to protect wood andwood composites from fungal attack. For example, it is known to use zincborate to protect cellulosic composites, including particleboard,hardboard and oriented strand board, from fungal decay, as described inU.S. Pat. Nos. 4,879,083; 5,763,338; and 5,972,266. However, like mostborates, zinc borate is not particularly effective against mold fungi.Recent work by Kop-Coat, Inc. (U.S. Pat. No. 6,416,789) has shown thatcombinations of IPBC, amine oxides and borates have a synergistic effectagainst many types of fungus in panel products such as OSB andhardboard.

Beginning in the 1930s, the sodium salt of pentachlorophenol (PCP) wasthe chemical of choice in preventing sapstain discoloration in freshlysawn lumber. By the mid-1980s, PCP was restricted for this use due toconcerns over safety and environmental impact. This led to thedevelopment of a number of substitutes based on preservatives such asTCMTB, IPBC and DDAC. One of the leading antisapstain formulas continuesto be NP-1®, a synergistic mixture of IPBC and DDAC (U.S. Pat. No.4,950,685). New formulas have been developed in recent years. Theperformance of many of these has been evaluated by Oregon StateUniversity. (See Forest Products Journal Vol. 52, No. 2, pp53–61 for areview of recent formulas.)

Since the 1940s, the main products for pressure treating have beencreosote, PCP in fuel oil and CCA. In February 2002, the U.S. EPArestricted the use of CCA in residential applications of pressuretreated wood, effective Dec. 31, 2003. Alternative treatments includeborates, copper azole and ACQ.

Millwork treatment is a non-pressure application of preservatives toprotect against mildew and decay. Solid lumber or wood composites aregenerally dipped in millwork treating solutions which also contain waterrepellents. WDMA Standard I.S. 4-2000 covers the preservative treatmentof millwork components. Products approved under WDMA HallmarkCertification Program are based on TBTO, IPBC, TCMTB, propiconazole andtebuconazole. Synergistic anti-fungal combinations of propiconazole andtebuconazole are the subject of U.S. Pat. No. 5,223,524.

In recent years, there have been increasing concerns about mold growthin indoor residential environments. Mold can be a respiratory allergento some individuals and is suspected of being a toxin in extremeexposure situations, although evidence of toxicity to humans is inquestion. Manufacturers of panel products such as OSB are taking stepsto reduce or eliminate the possibility of mold growth on theirmaterials. Potlatch Corporation has introduced OX-Terminator, a woodpreservative treated panel product. See, e.g., International ApplicationPublication No. WO 01/79339 A1. The active ingredient is based on acopper ammonium complex.

It is also known to use iodopropargyl derivatives such as3-iodo-2-propynyl-n-butyl carbamate (IPBC) for protection against fungiwhich cause structural and cosmetic damage to wood. However, whileeffective, this compound used alone is expensive and requires largeramounts to achieve the desired end result.

U.S. Pat. No. 5,389,300 provides a composition for protecting sawntimber against wood discoloring fungi, containing a phenol fungicide anda halopropynyl fungicide such as IPBC. Other fungicides, insecticides,or active ingredients, including boron compounds, can be added to thecomposition.

U.S. Pat. No. 5,846,305 discloses a wood preservative compositioncomprising a copper compound, an amine solvent and a boron compound. Thepreferred boron compound is sold by U.S. Borax, Inc. under the tradename“TIMBOR.”

U.S. Pat. No. Re36,798 provides a preservative composition for treatmentof wood and other cellulosic materials, comprising a biocidal metalcompound and a fungicidal compound containing a triazole group.Compositions of this invention may contain other organic fungicides,insecticides, or bactericides, including boron in any form, such asboric acid, boron, or boron esters.

U.S. Pat. No. 4,950,685 relates to a wood preservative composition whichprovides stain resistance to wood. The composition comprises asynergistic combination of a quaternary ammonium compound and IPBC.

U.S. Pat. No. 5,990,043 relates to an anti-fouling composition whichincludes a carrier, a binder, and an effective amount of at least oneinsecticide, which can be a carbamate. Synergistic effects are observedwhen combinations of two or more of the numerous insecticides listed areused in combination.

It is desired, therefore, to develop a wood treatment substance capableof protecting wood against fungal decay, mold and mildew in aneconomical, safe and environmentally responsible manner.

SUMMARY OF THE INVENTION

The present invention fulfills the above need by providing an unusuallyeffective and economical wood treatment that protects wood and woodproducts against fungal decay, mold and mildew. The present inventionprovides unique combinations of four classes of fungicides, specificallyazole compounds, halopropynyl compounds, amine oxide compounds anddiiodomethyl-p-tolylsulfone, which in combination provide a morecomplete resistance to decay, in a more economical manner, than use ofany of these compounds individually. A method of treating wood, inparticular composite wood materials, with the synergistic combination isincluded in the present invention, as is the wood treated by thiscombination.

Depending on the desired level of protection, combinations of two orthree compounds can also be used.

The present invention offers a meaningful advantage over many currentlyutilized wood preservative products. It has a favorablehealth/safety/environmental profile, and it offers a very cost-effectivemethod of protecting wood and wood-based composites from various formsof fungal attack.

It is an object of the invention therefore, to provide a combination offungicides to resist decay, mold and mildew in wood treated with suchsubstances, in an economical manner.

It is a further object of the present invention to provide an economicalwood treatment which can resist decay using azoles in combination withhalopropynyl, amine oxide and diiodomethyl-p-tolylsulfone.

It is an additional object of the present invention to provide a methodof treating wood using this synergistic combination of fungicides.

It is an additional object of the present invention to provide woodtreated with a synergistic combination of fungicides.

It is an additional object of the present invention to provide a woodtreatment composition that is biodegradable in soil and has an excellentworker safety and environmental profile.

These and other objects of the invention will become apparent from thefollowing description and appended claims.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Accordingly, the present invention provides a wood treatment compositioncomprising a synergistic combination of an azole compound, ahalopropynyl compound, an amine oxide compound anddiiodomethyl-p-tolylsulfone. As used herein, the term “wood treatmentcomposition” refers to this synergistic combination of fungicides, whichmay be used with other additives such as resins or solvents, and whichis applied to wood by a variety of methods including, but not limitedto, spraying, dipping, pressure treating, addition to wood furnishduring formation of wood composites, and other methods used to applysuch substances to wood and are known to those skilled in the art.

As used herein, an azole compound refers to a 1,2,4-triazole. Suitableazoles include, but are not limited to, triadimefon, triadimenol,triazbutil, propiconazole, cyproconazole, difenoconazole,fluquinoconazole, tebuconazole, flusiazole, uniconazole, diniconazole,bitertanol, hexaconazole, azaconazole, flutriafol, epoxiconazole,tetraconazole, penconazole, and mixtures thereof.

As used herein, the term “halopropynyl compound” refers to a category ofhalopropynyl compounds known to have biocidal activity and to provideprotection against fungi when applied to wood and other materials.

Suitable examples of halopropynyl compounds which may be used in thepresent invention include, but are not limited to, iodopropargylderivatives including compounds derived from propargyl or iodopropargylalcohols such as the esters, ethers, acetals, carbamates and carbonatesand the iodopropargyl derivatives of pyrimidines, thiazolinones,tetrazoles, triazinones, sulfamides, benzothiazoles, ammonium salts,carboxamides, hydroxamates, and ureas. This class of compounds has thegeneral formula:

wherein R is selected from the group consisting of hydrogen, substitutedand unsubstituted alkyl groups having from 1 to 20 carbon atoms,substituted and unsubstituted aryl, alkyl aryl, and aralkyl groupshaving from 6 to 20 carbon atoms and from substituted and unsubstitutedcycloalkyl and cycloalkenyl groups of 3 to 10 carbon atoms, and m and nare independently integers from 1 to 3, i.e., m and n are notnecessarily the same.

Preferred are formulations where m is 1 and n is 1 having the followingformula:

Suitable R substituents include alkyls such as methyl, ethyl, propyl,n-butyl, t-butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, dodecyl,octadecyl, cycloalkyls such as cyclohexyl, aryls, alkaryls and aralkylssuch as phenyl, benzyl, tolyl, cumyl, halogenated alkyls and aryls, suchas chlorobutryl and chlorophenyl, and alkoxy aryls such as ethoxyphenyland the like.

Compounds of this formula include iodopropargyl carbamates such as3-iodo-2-propynyl propyl carbamate, 3-iodo-2-propynyl butyl carbamate,3-iodo-2-propynyl hexyl carbamate, 3-iodo-2-propynyl cyclohexylcarbamate, 3-iodo-2-propynyl phenyl carbamate, and mixtures thereof.Most preferred is 3-iodo-2-propynyl butyl carbamate (IPBC).

As used herein, the term “amine oxide compound” refers to thosecompounds which are formed as reaction products in the reaction oftertiary amines and hydrogen peroxides and are represented by thegeneral formula:

where R₁, R₂ and R₃ are independent and can be a linear, branched,cyclic, aromatic or any combination thereof of saturated or unsaturatedC₁ to C₂₀ group and any C₂–C₂₀ carbon atom can be replaced with ahetero-atom selected from the group consisting of O, S and N.

Preferred amine oxides are alkyl dimethyl amine oxides such as decyldimethyl amine oxide, lauryl dimethyl amine oxide, isoalkyl dimethylamine oxide, myristyl dimethyl amine oxide, cetyl dimethyl amine oxide,stearyl dimethyl amine oxide and octyl dimethyl amine oxide. Mostpreferred is N-alkyl(C12–C16)—N, N-dimethylamine oxide (ADO).

As used herein, the term “wood” includes a variety of wood andwood-based materials, including, but not limited to, logs, dried lumber,green lumber, fiberboard, strand board, laminated veneer lumber,cellulosic composites, plastic wood composites and other types of wood,wood composites and engineered wood formed from wood flakes, chips,strands, veneers and adhesives. The wood treatment composition may beapplied to any wood substrate to prevent sapstain and other types offungal attack. With green lumber, meaning freshly cut or unseasonedlumber, it is desirable to control sapstain and mold.

Typically, the four compounds are mixed together sequentially withsolvents and other additives, the mixing comprising light agitation, toobtain a clear solution after each addition. Thediiodomethyl-p-tolylsulfone must be mixed with the amine oxide in thefirst step and agitated until a clear solution is obtained. The order ofaddition of the other ingredients is otherwise unimportant.

Any organic solvent can be used, but polar organic solvents arepreferred as they will provide better solubilization of the halopropynylcompound. Additional suitable solvents include, but are not limited to,alcohols, glycols, esters, ethers, polyethers and amines. Most preferredare solvents such as dipropylene glycol monomethyl ether.

Other constituents of the solution may include wax emulsion or otherwater repellant, solvents and/or water. Additional additives may also beused, and suitable additives include, but are not limited to, corrosioninhibitors, iron stain inhibitors, wetting agents, adhesives,emulsifiers, fillers, carriers, viscosity regulators, colorants, pHregulators, binders, tackifiers, and mixtures of any of these.

In a method of creating the wood product, the fungicide mixture can beapplied on the surface of the wood, as in spraying or dipping the woodin a formulation containing all four fungicides. The fungicides can alsobe applied to the wood with pressure treatment that is commonly used onsolid or engineered wood. Another method, particularly for woodcomposites, is to treat the wood chips, flakes or strands with thefungicide combination in powder or liquid form prior to formation of thecomposite wood boards.

In this method, the fungicides are combined with wood flakes, chips orstrands, an adhesive such as a phenolic or isocyanate resin or othersimilar resin known to those skilled in the art, and a water repellantand fabricated into a wood composite board. This last step may beaccomplished in a heated high-pressure press.

Wood may be treated by more than one of these methods, and as usedherein the term “treatment” refers to any one of these or other methodsknown to those skilled in art and which are used to apply these orsimilar substances to wood. Other suitable methods include, but are notlimited to, spraying, soaking, immersing, vacuum impregnation andbrushing, in addition to those already described.

Typically, the wood treatment composition of the present invention willbe prepared in concentrate form, and will be diluted prior toapplication to the wood. As used herein, the term “treating solution”will refer to the wood treatment composition after dilution, as appliedto wood.

In concentrate form, the wood treatment composition will comprise about0.1 to 10% by weight of an azole compound, about 0.1 to 10% by weight ofa halopropynyl compound, about 0.1 to 10% by weight ofdiiodomethyl-p-tolylsulfone, and about 5 to 90% by weight of an amineoxide, based upon 100% by weight of the total wood treatmentcomposition. Preferred ranges for amounts of each of the azole,halopropynyl compounds and diiodomethyl-p-tolylsulfone are about 0.1 to8% by weight of the total composition; most preferred is 0.2 to 6% byweight. The preferred range for the amine oxide is about 10 to 60%, morepreferably about 25 to 45%, based on 100% by weight of the total woodtreatment composition.

The combination of three of the active ingredients, the azole andhalopropynyl compounds and the diiodomethyl-p-tolylsulfone, willcomprise about 0.1 to about 30% by weight of the total wood treatmentcomposition in concentrate form, more preferably 0.1 to 20%, mostpreferably 0.1 to 10%. Thus, as will be understood by one skilled in theart, when less than all three of these compounds are used, the amountsof the remaining ingredients must be adjusted upward to provide thedesired overall concentration of active ingredients.

A treating solution, as that term is defined above, can be made from theconcentrate wood treatment composition, at the desired dilution level.For example, the concentrate can be diluted with water in a ratio of300:1 (water:concentrate), 200:1, 150:1, or other dilution ratio. Theappropriate dilution level can be determined by one skilled in the art,based on financial considerations, the type of wood being treated, theenvironmental conditions, and the length of time protection is desired.The amount of each ingredient in the treating solution will thus be theconcentrate amount divided by the dilution ratio, for example, if thehalopropynyl compound is present in the concentrate in an amount of 8%,based on the total weight of the concentrate, then the amount in thetreating solution after a 150:1 dilution will be 0.053% by weight.

In an additional embodiment, less than all four of the fungicides may beused in various combinations of two or three fungicides. For example,suitable combinations include the iodo-sulfone with a halopropynylcompound, iodo-sulfone with an azole, or iodo-sulfone with an amineoxide. IPBC can be used in combination with an azole, or in combinationwith an amine oxide. This list is not meant to be exhaustive, and use ofother combinations of two or three of the above fungicides as a woodtreatment composition is contemplated in the present invention. It willbe understood by one skilled in the art that depending on theenvironment in which the treated wood will be used, the type of wood(e.g., green lumber vs. dried lumber), the time duration of protectiondesired, cost of ingredient, and other similar factors, that use of lessthan all four ingredients may be desirable and may provide sufficientprotection against fungal attack.

The invention is further defined in the following non-limiting examples.

EXAMPLE 1

One (1) g of Amical 48 (97–99% diiodomethyl-p-tolyl-sulfone, availablefrom Dow Chemical) and 62.00 g of Barlox 1260PG (60% N-alkyl(C12–C16)-N,N-dimethylamine oxide, 25% propylene glycol, 15% water,available from Lonza), were added together and mixed until solution wasclear. 8.25 g of Glycol DPM (100% dipropylene glycol monomethyl ether,available from Shell, Arco Chemical) was added to mixer and allowed tomix until solution was clear. 0.1 g of a defoamer was added to themixture and mixed until completely dispersed. 1.0 g of a deodorizer wasadded to mixture, and the entire solution was mixed until clear. 8.75 gof Polyphase AF-1 (40% 3-iodo-2-propynyl-n-butyl carbamate, availablefrom Troy Chemical Co.) was added to mix and agitated until solution isclear. 7.0 g of Wocosen 50 TK (50% propiconazole, 50% dipropylene glycolmonomethyl ether, available from Janssen) was added to tank mixture andthen agitated until solution was clear. Finally, 11.90 g of a surfactantwas added to the tank and mixed for 30 minutes until a clear solutionwas obtained.

TABLE 1 50 to 1 100 to 1 150 to 1 200 to 1 300 to 1 Formula Amical0.02000 0.01000 0.00667 0.00500 0.00333 Wocosen 50 TK 0.14000 0.070000.04667 0.03500 0.02333 Polyphase AF-1 0.17500 0.08750 0.05833 0.043750.02917 Barlox 12-60PG 1.24000 0.62000 0.41333 0.31000 0.20667 InertsGlycol DPM 0.16500 0.08250 0.05500 0.04125 0.02750 Surfactant 0.238000.11900 0.07933 0.05950 0.03967 Deodorizer 0.02000 0.01000 0.006670.00500 0.00333 Defoamer 0.00200 0.00100 0.00067 0.00050 0.00033

TABLE 2 FORMULATION NUMBER: KC30-21 PRODUCT NAME: PERCENT BY RAWMATERIAL WEIGHT WEIGHT Amical 1.000 1.000 Wocosen 50 TK 7.000 7.000Polyphase AF-1 9.000 9.000 Barlox 12 61.750 61.750 Glycol DPM 8.2508.250 Surfactant 11.900 11.900 Deodorizer 1.000 1.000 Defoamer 0.1000.100 TOTAL WEIGHT 100.000 100.000 AMICAL 1.000 IPBC 3.500 Propiconazole3.500 Amine Oxide 37.050 Total Actives 45.050

EXAMPLE 2

Antisapstain Control—Laboratory Test

1. Samples were prepared as follows:

Samples were taken from Red Pine branches approximately 10 mm indiameter after the bark was removed and cut into 2–4 mm thickness.Samples were treated (30 second dip) in the various preservativetreatments and then allowed to air dry for one hour. Samples were thenput into the test and were not sterilized.

2. Preparation of Cultures

Pure or group cultures were propagated at least four days in advance ona 7 cm filter paper soaked with 3 ml nutrient solution in a test tube.After growth covered the filter paper, 15 ml of sterile distilled waterwas added to the tube and macerated until the sample was homogenized.

3. Preparation of Test Chamber

The test chamber was a petri dish with a connecting duct to a waterreservoir and a lid with an 0.2 mm micropore vapor port. The reservoirwas taped to the petri dish with heat resistant tape, and then filledwith distilled water. A piece of cellulose sponge was inserted into thereservoir duct. These dishes were sterilized in an autoclave for 45minutes at 121° C. Next, an adequate number (about 50) of ashless 7 cmfilter paper was placed in a container of nutrient solution, which wasthen sterilized in the autoclave for 45 minutes at 121° C. Three piecesof ashless 7 cm filter paper soaked in nutrient solution were added tothe dish, making sure that the filter paper and sponge made contact andthat the filter paper was centered in the dish.

4. Test Completion

Samples were added to the test chamber, out of contact with each otherand arranged in a circular pattern within the chamber. The samples werenot sitting on the filter paper, but overlapped the paper by a fewmillimeters. Culture inoculum, 1.0 ml deuteromycete fungi blend, wasadded to the center of the filter paper. The dishes were then incubatedat 26°–32° C. and 70%–90% relative humidity.

5. Evaluation

At five and fifteen days, the samples were evaluated. Evaluations weremade visually using a scale from −10 to 10. Minus ten (−10) indicates aninhibitory zone around the sample, and the sample is not infected. Ten(10) indicates a sample covered with mycellium.

Analysis of Results

Evaluations were converted from the scale (−10 to 10) to expresspercentage of wood surface area protected using the following equation:[(Visual Evaluation)−10]×(−10)=Percentage of wood Surface AreaProtected. After conversions, one way analyses of variance (ANOVA) andStudent's t-Test were used to test for treatment differences at adetermined rate of probability. A percent protection level that isgreater than 100% indicates that a zone of inhibition was providedaround the sample. The maximum value is 200%.

Fungi Used for Testing

Economic ATC Class Biological Class Organism Number Soft RotDeuteromycete Acremonium strictum A10141 Soft Rot Chaetomium globosum6021 Soft Rot Graphium rubrum 6506 Mold Trichoderma sp. K2 MoldTrichoderma viride 13631 Mold Aspergillus niger A1004 Mold Aspergillussp. K1 Mold Paecilomyces varioti 16023 Mold Gliocladium sp. K3 MoldCephaloascus fragrans 24950 Mold Alternaria alternata 13963 MoldPenicillium purpurogenum 52427 Mold Cladosporum cladosprioides 16022Stain Deuteromycete Aureobasidium pullulans 16622 Stain Diplodiagossypina 9055 Stain Chlorociboria aeruginascens 24028 Stain AscomyceteCeratocystis (Ophiostoma) picea 387A Stain Ceratocystis (Ophiostoma)14503 fimbriata Stain Ceratocystis (Ophiostoma) 18086 clavigerumK-200 Laboratory Test Results

TABLE 3 Concentrations of Active Ingredients Diluted 50:1 v/v with waterPercent Surface 3-iodo-2- Protection- Diiodomethyl- Pro- propynyl butylAmine Deuteromycete p-tolylsulfone piconazole carbamate Oxide Blend ofFungi 1.0 3.5 3.5 37.05 108A 8.0 37.05 91B 8.0 37.05 90B 8.0 37.05 92B1.0 3.5 3.5 72C 45.05 60D Untreated 0E Averages ending in the sameletter are statistically equal at a 95% confidence level.

TABLE 4 Concentrations of Active Ingredients Diluted 100:1 v/v withwater Percent Surface 3-iodo-2- Protection- Diiodomethyl- Pro- propynylbutyl Amine Deuteromycete p-tolylsulfone piconazole carbamate OxideBlend of Fungi 1.0 3.5 3.5 37.05 105A 8.0 37.05 86B 8.0 37.05 86B 8.037.05 85B 1.0 3.5 3.5 65C 45.05 49D Untreated 0E Averages ending in thesame letter are statistically equal at a 95% confidence level.

TABLE 5 Concentrations of Active Ingredients Diluted 150:1 v/v withwater Percent Surface 3-iodo-2- Protection- Diiodomethyl- Pro- propynylbutyl Amine Deuteromycete p-tolylsulfone piconazole carbamate OxideBlend of Fungi 1.0 3.5 3.5 37.05 100A 8.0 37.05 79B 8.0 37.05 66C 8.037.05 82B 1.0 3.5 3.5 42D 45.05 45D Untreated 0E Averages ending in thesame letter are statistically equal at a 95% confidence level.

TABLE 6 Concentrations of Active Ingredients Diluted 200:1 v/v withwater Percent Surface 3-iodo-2- Protection- Diiodomethyl- Pro- propynylbutyl Amine Deuteromycete p-tolylsulfone piconazole carbamate OxideBlend of Fungi 1.0 3.5 3.5 37.05 95A 8.0 37.05 70B 8.0 37.05 59C 8.037.05 74B 1.0 3.5 3.5 39D 45.05 32D Untreated 0E Averages ending in thesame letter are statistically equal at a 95% confidence level.

TABLE 7 Concentrations of Active Ingredients Diluted 300:1 v/v withwater Percent Surface 3-iodo-2- Protection- Diiodomethyl- Pro- propynylbutyl Amine Deuteromycete p-tolylsulfone piconazole carbamate OxideBlend of Fungi 1.0 3.5 3.5 37.05 79A 8.0 37.05 49B 8.0 37.05 45BC 8.037.05 56B 1.0 3.5 3.5 332C 45.05 12DE Untreated 0E Averages ending inthe same letter are statistically equal at a 95% confidence level.

TABLE 8 Bioassay Results Concentrations of Active Ingredients Diluted150:1 v/v with Water Percent Surface 3-iodo-2- Protection- Diiodomethyl-propynyl Butyl Deuteromycete p-tolylsulfone Propiconazole CarbamateAmine Oxide Blend of Fungi 8.0 (0.053) 37E 4.0 (0.027) 34E 2.0 (0.013)12F 8.0 (0.053) 79C 4.0 (0.027) 62D 2.0 (0.013) 12F 8.0 (0.053) 86B 4.0(0.027) 69DC 2.0 (0.013) 31E 22.525 (0.150) 13F 37.05 (0.247) 48D 45.05(0.300) 51D 67.575 (0.451) 59D 8.0 (0.053) 37.05 (0.247) 75C 8.0 (0.053)37.05 (0.247) 82BC 8.0 (0.053) 37.05 (0.247) 89B 4.0 (0.027) 4.0 (0.027)44D 4.0 (0.027) 4.0 (0.027) 90B 4.0 (0.027) 4.0 (0.027) 76C 1.0 (0.007)7.0 (0.047) 80BC 1.0 (0.007) 7.0 (0.047) 84BC 4.0 (0.027) 4.0 (0.027)37.05 (0.247) 92B 4.0 (0.027) 4.0 (0.027) 37.05 (0.247) 74C 1.0 (0.007)3.5 (0.023) 3.5 (0.023) 46D 1.0 (0.007) 7.0 (0.047) 37.05 (0.247) 82BC1.0 (0.007) 7.0 (0.047) 37.05 (0.247) 92B 0.5 (0.003) 1.75 (0.012) 1.75(0.012) 22.525 (0.150) 64CD 1.0 (0.007) 3.5 (0.023) 3.5 (0.023) 37.05(0.247) 102A 1.0 (0.007) 3.5 (0.023) 3.5 (0.023) 45.05 (0.300) 104A 1.5(0.01) 5.25 (0.035) 5.25 (0.035) 67.575 (0.451) 112A 0.25 (002) 0.875(0.0058) 0.875 (0.0058) 37.05 (0.451) 73C 0.5 (0.003) 1.75 (0.012) 1.75(0.012) 37.05 (0.247) 89B 1.0 (0.007) 3.5 (0.023) 3.5 (0.023) 37.05(0.247) 100A 1.5 (0.01) 5.25 (0.035) 5.25 (0.035) 37.05 (0.247) 105AUntreated 0

EXAMPLE 3

Field Test Data

The dimensions of the wood samples are typically 2 in. by 4 in. and 0.5m in length. Hardboards such as Red Oak and Gum typically varied inwidth. Boards were cut and then randomly selected from the various woodspecies. 25 samples of each treatment were used for testing. An endeavorwas made to select only sapwood to ensure heartwood had a minimal affecton later assessments.

Preservative retentions of solutions were taken at the beginning and atthe end of testing. Solution pick-up is measured before and after woodsamples are dipped into treating solution.

The following results in Table 9 show how the present invention providesunique protection against sapstain fungi in the field when compared tothe industry standard NP-1 (7.6% IPBC, 64.8% DDAC).

Test samples were observed for fungal growth. The percentage of attackon the surface of the samples was recorded. A 0% (No attack)100%(complete attack) rating scale was used.

TABLE 9 Species Hemlock Douglas Fir Southern Yellow Pine Gum Red OakRadiata Pine % v/v * % v/v * % v/v * % v/v * % v/v * % v/v * 7.6% IPBC,64.8% DDAC  4 weeks 1.0 9.3 1.0 13.2 1.0 22.0 0.67 45.2 0.67 2.0 1.0 1.10.67 12.3 0.67 16.0 0.67 35.2 0.5 30.0 0.5 12.0 0.67 5.0 0.5 36.2 0.536.0 0.5 38.0 0.4 29.2 0.4 18.0 0.5 8.0 12 weeks 1.0 17.0 1.0 16.8 1.039.75 0.67 52.0 0.67 5.0 1.0 5.0 0.67 24.8 0.67 28.32 0.67 43.25 0.545.5 0.5 15.0 0.67 8.0 0.5 40.97 0.5 52.16 0.5 45.50 0.4 37.25 0.4 25.50.5 12.0 1.0% DIMPS, 3.5% IPBC, 3.5% Propiconazole, 37.05% Amine Oxide 4 weeks 1.0 5.0 1.0 15.2 1.0 8.0 0.67 2.0 0.67 0.0 1.0 1.0 0.67 8.20.67 16.2 0.67 12.0 0.5 1.9 0.5 8.0 0.67 2.0 0.5 9.2 0.5 24.2 0.5 18.00.4 4.0 0.4 10.0 0.5 3.0 12 weeks 1.0 11.84 1.0 23.28 1.0 14.75 0.673.75 0.67 0.5 1.0 2.0 0.67 15.56 0.67 23.92 0.67 38.0 0.5 4.00 0.5 20.00.67 3.2 0.5 15.52 0.5 27.76 0.5 38.25 0.4 8.50 0.4 17.0 0.5 5.0 2.0%DIMPS, 3.0% IPBC  4 weeks 1.0 22.0 1.0 25.2 1.0 32.0 0.67 12.0 0.67 31.21.0 15.0 0.67 45.2 0.67 45.2 0.67 55.0 0.5 26.3 0.5 44.1 0.67 16.0 0.542.1 0.5 49.3 0.5 62.0 0.4 42.0 0.4 49.0 0.5 22.0 12 weeks 1.0 38.0 1.036.2 1.0 62.0 0.67 33.5 0.67 47.4 1.0 22.0 0.67 50.0 0.67 57.8 0.67 65.00.5 31.8 0.5 52.0 0.67 18.0 0.5 45.0 0.5 54.6 0.5 72.0 0.4 45.3 0.4 55.10.5 39.0 4.0% IPBC  4 weeks 1.0 22.2 1.0 36.2 1.0 40.0 0.67 19.0 0.6712.0 1.0 42.0 0.67 26.3 0.67 45.2 0.67 55.3 0.5 22.0 0.5 32.0 0.67 51.00.5 45.2 0.5 55.2 0.5 65.1 0.4 35.1 0.4 35.0 0.5 63.1 12 weeks 4.0%IPBC, 27.0% Amine Oxide  4 weeks 1.0 12.2 1.0 36.2 1.0 12.0 0.67 5.90.67 5.0 1.0 28.0 0.67 15.2 0.67 45.2 0.67 26.3 0.5 7.2 0.5 16.0 0.6732.0 0.5 25.3 0.5 49.2 0.5 42.0 0.4 9.0 0.4 22.0 0.5 45.2 12 weeks 1.020.7 1.0 47.4 1.0 33.5 0.67 9.3 0.67 15.0 1.0 35.0 0.67 28.7 0.67 52.00.67 31.8 0.5 13.4 0.5 32.0 0.67 55.0 0.5 53.9 0.5 55.12 0.5 45.3 0.416.0 0.4 38.0 0.5 62.0 5.0% DIMPS  4 weeks 1.0 26.2 1.0 36.2 1.0 32.00.67 34.2 0.67 12.0 1.0 10.0 0.67 29.2 0.67 45.2 0.67 45.0 0.5 41.1 0.516.0 0.67 6.0 0.5 46.3 0.5 45.9 0.5 60.0 0.4 47.1 0.4 21.0 0.5 20.0 12weeks 1.0 49.3 1.0 51.8 1.0 52.0 0.67 46.0 0.67 22.5 1.0 33.0 0.67 47.40.67 54.4 0.67 62.0 0.5 52.1 0.5 20.0 0.67 11.1 0.5 45.5 0.5 50.7 0.575.0 0.4 53.0 0.4 32.5 0.5 32.0 *Rating System = 0–100 Percent Attackv/v = volume liquid/volume liquid basisIt will be appreciated that the present invention provides a woodtreatment material having a synergistic combination of fungicidesincluding an azole compound, a halopropynyl compound, an amine-oxide,and diiodomethyl-p-tolylsulfone, which is especially effective inproviding resistance to decay, mold and mildew when wood is treated withthis combination. While particular embodiments of this invention havebeen described above for purposes of illustration, it will be evident tothose skilled in the art that numerous variations of the details of thepresent invention may be made without departing from the invention asdefined in the appended claims.

1. A fungicidal wood treatment composition in concentrate formcomprising from about 0.1 to 10% by weight of an azole compound, about0.1 to 10% by weight of a halopropynyl compound, about 0.1 to 10% byweight of diiodomethyl-p-tolylsulfone, and about 5 to 90% by weight ofan amine oxide, based upon 100% by weight of the total wood treatmentcomposition.
 2. The composition of claim 1, wherein the azole compoundis a 1,2,4-triazole.
 3. The composition of claim 2, wherein the azole isselected from the group consisting of triadimefon, triazbutil,propiconazole, cyproconazole, difenoconazole, fluquinoconazole,tebuconazole, flusiazole, uniconazole, diniconazole, bitertanol,hexaconazole, azaconazole, flutriafol, epoxiconazole, tetraconazole,penconazole, and mixtures thereof.
 4. The composition of claim 3,wherein the azole is propiconazole.
 5. The composition of claim 3,wherein the azole is selected from the group consisting of azaconazoleand hexaconazole.
 6. The composition of claim 1, wherein thehalopropynyl compound is represented by the formula:

and R is selected from the group consisting of hydrogen, substituted andunsubstituted alkyl groups having from 1 to 20 carbon atoms, substitutedand unsubstituted aryl, alkyl aryl, and aralkyl groups having from 6 to20 carbon atoms and from substituted and unsubstituted cycloalkyl andcycloalkenyl groups of 3 to 10 carbon atoms, and m and n areindependently integers from 1 to
 3. 7. The composition of claim 6,wherein the halopropynyl compound is selected from the group consistingof 3-iodo-2-propynyl propyl carbamate, 3-iodo-2-propynyl butylcarbamate, 3-iodo-2-propynyl hexyl carbamate, 3-iodo-2-propynylcyclohexyl carbamate, 3-iodo-2-propynyl phenyl carbamate, and mixturesthereof.
 8. The composition of claim 7, wherein the halopropynylcompound is 3-iodo-2-propynyl butyl carbamate.
 9. The composition ofclaim 1, wherein the amine oxide compound is represented by the formula:

where R₁, R₂ and R₃ are independent and can be linear, branched, cyclic,aromatic or any combination thereof of saturated or unsaturated C₁ toC₂₀ group and any C₂–C₂₀ carbon atom can be replaced with a heteroatomselected from the group consisting of O, S and N.
 10. The composition ofclaim 9, wherein the amine oxide compound is selected from the groupconsisting of decyl dimethyl amine oxide, lauryl dimethyl amine oxide,isoalkyl dimethyl amine oxide, myristyl dimethyl amine oxide, cetyldimethyl amine oxide, stearyl dimethyl amine oxide, octyl dimethyl amineoxide, N-alkyl(C12–C16)—N, N-dimethylamine oxide and mixtures thereof.11. The composition of claim 10, wherein the amine oxide compound isN-alkyl(C12–C16)-N,N-dimethylamine oxide.
 12. The composition of claim1, wherein the azole is propiconazole, the halopropynyl compound is3-iodo-2-propynyl-n-butylcarbamate, and the amine oxide compound isN-alkyl(C12–C16)-N,N-dimethylamine oxide.
 13. The composition of claim1, further comprising a solvent.
 14. The composition of claim 1, furthercomprising water.
 15. The composition of claim 13, wherein the solventis selected from the group consisting of alcohols, glycols, esters,ethers, polyethers, and mixtures thereof.
 16. The composition of claim1, further comprising an additive.
 17. The composition of claim 16,wherein the additive is selected from the group consisting of acorrosion inhibitor, iron stain inhibitor, wetting agent, colorant,adhesive, emulsifier, filler, carrier, viscosity regulator, pHregulator, binder, tackifier, and mixtures thereof.
 18. A method oftreating wood comprising treating wood with a composition in concentrateform comprising from about 0.1 to 10% by weight of an azole compound,about 0.1 to 10% by weight of a halopropynyl compound, about 0.1 to 10%by weight of diiodomethyl-p-tolylsulfone, and about 5 to 90% by weightof an amine oxide, based upon 100% by weight of the total wood treatmentcomposition.
 19. The method of claim 18, wherein the azole compound is a1,2,4-triazole.
 20. The method of claim 19, wherein the azole isselected from the group consisting of triadimefon, triazbutil,propiconazole, cyproconazole, difenoconazole, fluquinoconazole,tebuconazole, flusiazole, uniconazole, diniconazole, bitertanol,hexaconazole, azaconazole, flutriafol, epoxiconazole, tetraconazole,penconazole, and mixtures thereof.
 21. The method of claim 20, whereinthe azole is propiconazole.
 22. The method of claim 20, wherein theazole is selected from the group consisting of azaconazole andhexaconazole.
 23. The method of claim 18, wherein the halopropynylcompound is represented by the formula:

and R is selected from the group consisting of hydrogen, substituted andunsubstituted alkyl groups having from 1 to 20 carbon atoms, substitutedand unsubstituted aryl, alkyl aryl, and aralkyl groups having from 6 to20 carbon atoms and from substituted and unsubstituted cycloalkyl andcycloalkenyl groups of 3 to 10 carbon atoms, and m and n areindependently integers from 1 to
 3. 24. The method of claim 23, whereinthe halopropynyl compound is selected from the group consisting of3-iodo-2-propynyl propyl carbamate, 3-iodo-2-propynyl butyl carbamate,3-iodo-2-propynyl hexyl carbamate, 3-iodo-2-propynyl cyclohexylcarbamate, 3-iodo-2-propynyl phenyl carbamate, and mixtures thereof. 25.The method of claim 24, wherein the halopropynyl compound is3-iodo-2-propynyl butyl carbamate.
 26. The method of claim 18, whereinthe amine oxide compound is represented by the formula:

where R₁, R₂ and R₃ are independent and can be linear, branched, cyclic,aromatic or any combination thereof of saturated or unsaturated C₁ toC₂₀ group and any C₂–C₂₀ carbon atom can be replaced with a heteroatomselected from the group consisting of O, S and N.
 27. The method ofclaim 26, wherein the amine oxide compound is selected from the groupconsisting of decyl dimethyl amine oxide, lauryl dimethyl amine oxide,isoalkyl dimethyl amine oxide, myristyl dimethyl amine oxide, cetyldimethyl amine oxide, stearyl dimethyl amine oxide, octyl dimethyl amineoxide, N-alkyl(C12–C16)—N, N-dimethylamine oxide and mixtures thereof.28. The method of claim 27, wherein the amine oxide compound isN-alkyl(C12–C16)-N,N-dimethylamine oxide.
 29. The method of claim 18,wherein the azole is propiconazole, the halopropynyl compound is3-iodo-2-propynyl-n-butylcarbamate, and the amine oxide compound isN-alkyl(C12–C16)-N,N-dimethylamine oxide.
 30. The method of claim 18,wherein the wood treatment composition in treating solution formcomprises from about 0.001 to 10% by weight of an azole compound, about0.001 to 10% by weight of a halopropynyl compound, about 0.001 to 10% byweight of diiodomethyl-p-tolylsulfone, and about 0.01 to 90% by weightof an amine oxide, based upon 100% by weight of the total wood treatmentcomposition after dilution.
 31. The method of claim 18, the compositionfurther comprising a solvent.
 32. The method of claim 18, furthercomprising water.
 33. The method of claim 31, wherein the solvent isselected from the group consisting of alcohols, glycols, esters, ethers,polyethers, and mixtures thereof.
 34. The method of claim 18, thecomposition further comprising an additive.
 35. The method of claim 34,wherein the additive is selected from the group consisting of acorrosion inhibitor, iron stain inhibitor, wetting agent, colorant,adhesive, emulsifier, filler, carrier, viscosity regulator, pHregulator, binder, tackifier, and mixtures thereof.